Avars, a tribe of Turanian origin, who first appear in European history about the middle of the 6th century, when the bulk of them left their abodes between the Caspian and the Don, penetrated to the Danube, and settled in Dacia. They served in the army of Justinian, allied themselves with the Longobards against the Gepidae, and finally occupied Pannonia and other parts of modern Hungary, and established their dominion over the Slavs north and south of the Danube. Their sovereigns were called khans. The mightiest among them was Baian (570-630), whose dominions extended from the Elbe to the Black sea, and to whom the Byzantine emperors paid tribute. The Avars seized Dalmatia, and made inroads into Italy and into the heart of Germany. In 640 the Slavs revolted, and the dominion of the Avars over them came to an end; but they still maintained themselves in Pannonia. They allied themselves with Thassilo, duke of Bavaria, against Charlemagne; but that monarch finally broke their power (791 and 796). One of the Avar khans, Tudun, joined Charlemagne, and was baptized at Aix-la-Chapelle, but subsequently abandoned the emperor and fought against him until he was taken prisoner and beheaded. About 827 the Avars disappear wholly from history.

They have been confounded with their forerunners the Huns, and with their successors the Magyars. The modern Avars of Lesghistan in the Caucasus have also been erroneously considered their kindred. Remains of the long-walled camps of the mediaeval Avars are still to be seen near the Danube in Hungary.